@-webkit-keyframes pulse {
 0% {
   background-color: red;
   opacity: 1.0;
   -webkit-transform: scale(1.0) rotate(0deg);
   left: 20px;
 }
 33% {
   background-color: blue;
   opacity: 0.75;
   -webkit-transform: scale(1.5) rotate(-15deg);
   left: -20px;
 }
 67% {
   background-color: green;
   opacity: 0.5;
   -webkit-transform: scale(1.1) rotate(15deg);
   left: -200px;
 }
 100% {
   background-color: red;
   opacity: 1.0;
   -webkit-transform: scale(1.0) rotate(0deg);
   left: 100px;
 }
}

.pulsedbox {
 -webkit-animation-name: pulse;
 -webkit-animation-duration: 10s;
 -webkit-animation-iteration-count: infinite;
 -webkit-animation-timing-function: ease-in-out;
}

div {
  position: absolute;
  background-color: red;
  width: 40%;
  padding: 0.2em 1em;
  margin: 6em;
}